Bilateral Internal Thoracic Artery Grafting Increases Mediastinitis: Myth or Fact?

BACKGROUND: There is controversy about the risk of mediastinitis associated with the use of both internal thoracic arteries (ITA). METHODS: We performed a case-control study of patients operated on at a single institution from January 2003 to December 2014. A total of 3,118 consecutive patients undergoing isolated coronary artery bypass graft surgery were included; 81.3% (n = 2,533) underwent bilateral ITA (BITA) grafts exclusively and constitute the BITA group, and 18.7% (n = 585) constitute the single ITA (SITA) group. Mediastinitis was defined as deep tissue mediastinal infection, with clinical or microbiologic evidence. Continuous variables were expressed as mean ± SD, and categoric variables as percentage (range). Student's t test and Fisher's exact test were used, as appropriate. Propensity score matching analysis was performed according to the nearest neighbor estimation method (n = 1,040). RESULTS: The incidence of diabetes mellitus was similar in both groups (29%, p = 0.9). The BITA patients were more like to be younger (p < 0.001), men (p < 0.001), had a higher prevalence of hypertension (p < 0.01), higher body mass index (p < 0.001), lower prevalence of left ventricular dysfunction (p < 0.001) and of previous myocardial infarction (p < 0.01), and greater use of off-pump coronary artery bypass graft surgery (p < 0.01). The BITA patients had lower unadjusted hospital mortality (1.6%, versus 5.3% for SITA, p < 0.0001). The total incidence of mediastinitis was 1.8% (BITA 1.9% versus SITA 1.5%, p = 0.6). Diabetes (p < 0.01) and nonelective surgery (p = 0.004) were the only predictors of mediastinitis in the entire population. Propensity score matching showed no differences in mediastinitis: BITA 2.5% versus SITA 1.3% (p = 0.17). CONCLUSIONS: In this series of patients, BITA did not increase the risk of mediastinitis in the total population or in the propensity score matched subgroups.

Resultados a largo plazo de la plástica mitral en enfermedad degenerativa: prolapso posterior versus anterior o bivalvar / Long-Term Outcomes of Mitral Valve Repair in Degenerative Valve Disease: Comparison Between Posterior and Anterior or Bileaflet Mitral Valve Prolapse

Objetivo: Comparar la evolución clínica y ecocardiográfica de la plástica mitral secundaria a insuficiencia mitral degenerativa en pacientes con prolapso de la valva posterior versus prolapso anterior o bivalvar. Material y métodos: Entre abril de 1997 y julio de 2013 fueron intervenidos 255 pacientes por insuficiencia mitral moderada/ grave degenerativa. De ellos, 175 tenían compromiso de la valva posterior exclusivamente (Grupo 1) y 80 de la valva anterior 0 bivalvar (Grupo 2). No hubo diferencias en edad ni predominio de sexo entre los grupos. El seguimiento clínico se completó en el 95% de los casos con un promedio de 5,6 ± 3,8 años y el ecocardiográfico en el 77% con un promedio de 4,8 ± 3,7 años. Resultados: El éxito del procedimiento se alcanzó en el 87% de los casos (33 conversiones intraoperatorias a reemplazo valvular) (Grupo 1: 98% vs. Grupo 2: 62,5%; p < 0,01). La mortalidad hospitalaria global fue del 2,3% (6/255). La sobrevida a los 10 años fue del 92,0 ± 2,1% (Grupo 1: 94,4% ± 2,2% vs. Grupo 2: 86,3 ± 5,1%; p = 0,036). La libertad de reoperación a 10 años de seguimiento fue del 95,6 ± 1,6% (Grupo 1: 97,1 ± 1,4% vs. Grupo 2: 89,7 ± 5,0%; p = 0,035). La libertad de insuficiencia mitral moderada/grave en el ecocardiograma a los 10 años fue del 79,0 ± 4,4% (Grupo 1: 80,8 ± 4,8% vs. Grupo 2: 71,9 ± 9,6%; p = 0,14). El 91,2% de los pacientes se encontraban libres de síntomas a los 10 años (92% Grupo 1 vs. 89,3% Grupo 2; p = 0,5). Conclusiones: Los pacientes con plástica mitral secundaria a enfermedad degenerativa de la valva posterior tuvieron mayor sobrevida y una incidencia menor de reoperación en el seguimiento alejado. No hubo diferencias en libertad de insuficiencia mitral moderada/grave entre ambos grupos a 10 años de seguimiento.

Objective: The aim of this study is to compare the clinical and echocardiographic outcome of mitral valve repair secondary to degenerative mitral valve regurgitation in patients with posterior versus anterior or bileaflet mitral valve prolapse. Methods: Between April 1997 and July 2013, 255 patients underwent surgery for moderate to severe degenerative mitral valve regurgitation: 175 had posterior mitral valve prolapse (Group 1) and 80 had anterior or bileaflet mitral valve prolapse (Group 2). There were no differences in age or sex between the groups. Clinical follow-up was completed in 95% of the cases with a mean follow-up period of 5.6 ± 3.8 years and 77% completed echocardiographic follow-up with a mean of 4.8 ± 3.7 years. Results: The procedure was successful in 87% of cases (33 intraoperative conversions to mitral valve replacement) (Group 1: 98% vs. Group 2: 62.5%; p < 0.01). Overall in-hospital mortality was 2.3% (6/255), and 10-year survival was 92.0 ± 2.1% (Group 1: 94.4% ± 2.2% vs. Group 2: 86.3 ± 5.1%; p = 0.036). At 10-year follow-up, 95.6 ± 1.6% of patients were free from reoperation (Group 1: 97.1 ± 1.4% vs. Group 2: 89.7 ± 5.0%; p = 0.035), 79.0 ± 4.4% remained free from moderate to severe mitral regurgitation (Group 1: 80.8 ± 4.8% vs. Group 2: 71.9 ± 9.6%; p = 0.14) and 91.2% were asymptomatic (92% Group 1 vs. 89.3% Group 2; p = 0.5). Conclusions: Patients undergoing mitral valve repair secondary to degenerative posterior mitral valve prolapse had higher survival and lower incidence or reoperation in the long-term follow-up. There were no differences in freedom from moderate to severe mitral regurgitation between both groups at 10-year follow-up.